Figure 1.

Direct phenotypic responses to 11 generations of selecting bank voles towards (a) high swim-induced aerobic metabolism, (b) herbivorous capability measured as ability to maintain body mass in a test with low-quality diet, (c) predatory propensity measured as ranked time to attack a cricket, and (d) comparison of the cumulative effects of selection in the three directions expressed as a difference between the means of four selected (in each direction) and four control lines (expressed in units of phenotypic standard deviation). In generation 8, the food used in selection trial in the ‘herbivorous’ lines was different than in other generations, which resulted in the irregular pattern (marked with dashed lines and open symbols on graphs (b) and (d)). (Online version in colour.)